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All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Hemicellulose and starch citrate chitosan foam adsorbents for removal of arsenic and other heavy metals from contaminated water

Arsenic and other heavy metal contaminants in water are a significant global health threat. In this study, low-cost, sulfur-free, sustainable, water-insoluble materials with heavy metal remediation properties were produced from renewable resources such as starch, xylan, citric acid, and chitosan. Synthesized starch citrate-chitosan (SCC) foam and xylan citrate-chitosan (XCC) foam were flexible, porous, and elastic. The foams’ arsenic uptake in water was significantly greater than five different commercial metal remediating agents. The mercury and lead uptakes with the synthesized foams were similar to the performance of a commercial sulfur-based product, SorbaTech 450 (ST450). However, the cadmium and selenium uptakes were comparatively lower. The complexation of arsenic with oxygen and nitrogen of the SCC foam was shown with time-of-flight secondary ion mass spectrometry (TOF-SIMS). The XCC foam was also shown to adsorb potassium iodide (KI) at a similar rate to sodium chloride. This may be used to remediate water contaminated with radioactive materials, such as iodine 131.

Materials Science↗
DOE OSTI2022

Six-Month Outcomes of Infants Born to People With SARS-CoV-2 in Pregnancy

OBJECTIVES To assess the 6-month incidence of laboratory-confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, postnatal care, hospitalization, and mortality among infants born to people with laboratory-confirmed SARS-CoV-2 infection during pregnancy by timing of maternal infection. METHODS Using a cohort of liveborn infants from pregnancies with SARS-CoV-2 infections in the year 2020 from 10 United States jurisdictions in the Surveillance for Emerging Threats to Mother and Babies Network, we describe weighted estimates of infant outcomes from birth through 6 months of age from electronic health and laboratory records. RESULTS Of 6601 exposed infants with laboratory information through 6 months of age, 1.0% (95% confidence interval: 0.8–1.1) tested positive, 19.1% (17.5–20.6) tested negative, and 80.0% (78.4–81.6) were not known to be tested for SARS-CoV-2. Among those ≤14 days of age, SARS-CoV-2 infection occurred only with maternal infection ≤14 days before delivery. Of 3967 infants with medical record abstraction, breastmilk feeding initiation was lower when maternal infection occurred ≤14 days before delivery compared with >14 days (77.6% [72.5–82.6] versus 88.3% [84.7–92.0]). Six-month all-cause hospitalization was 4.1% (2.0–6.2). All-cause mortality was higher among infants born to people with infection ≤14 days (1.0% [0.4–1.6]) than >14 days (0.3% [0.1–0.5]) before delivery. CONCLUSIONS Results are reassuring, with low incidences of most health outcomes examined. Incidence of infant SARS-CoV-2, breastmilk feeding initiation, and all-cause mortality differed by timing of maternal infection. Strategies to prevent infections and support pregnant people with coronavirus disease 2019 may improve infant outcomes.

Pediatrics↗
DOE OSTI2021

Influence of Agricultural Managed Aquifer Recharge (AgMAR) and Stratigraphic Heterogeneities on Nitrate Reduction in the Deep Subsurface

This data package contains input files for TOUGHREACT for a modeling study examining the effects of managed aquifer recharge on agricultural lands on nitrate cycling and transport in the Central Valley of CA near Modesto. The files contain all the geochemical species, reactions, and hydrological parameters for the model. The files are text files used for the TOUGH family of code created by LBNL. To use the files a license is required. https://tough.lbl.gov/licensing-download/toughreact-licensing-download/Accompanying Paper Abstract: Agricultural managed aquifer recharge (AgMAR) is a proposed management strategy whereby surface water flows are used to intentionally flood croplands with the purpose of recharging underlying aquifers. However, legacy nitrate (NO3-) contamination in agriculturally-intensive regions poses a threat to groundwater resources under AgMAR. To address these concerns, we use a reactive transport modeling framework to better understand the effects of AgMAR management strategies (i.e., by varying the frequency, duration between flooding events, and amount of water) on N leaching to groundwater under different stratigraphic configurations and antecedent moisture conditions. In particular, we examine the potential of denitrification and nitrogen retention in deep vadose zone sediments (~15 m) using variable AgMAR application rates on two-dimensional representations of differently textured soils, soils with discontinuous bands/channels, and soils with preferential flow paths characteristic of typical agricultural field sites. Our results indicate that finer textured sediments, such as silt loams, alone or embedded within high flow regions, are important reducing zones providing conditions needed for denitrification. Simulation results further suggest that applying water all-at-once rather than in increments for a fixed volume of recharge transports higher concentrations of NO3- deeper into the profile, which has the potential to exacerbate groundwater quality. This transport into deeper depths can be aggravated by wetter antecedent soil moisture conditions. However, applying water all-at-once also increases denitrification within the vadose zone by promoting anoxic conditions. We conclude that AgMAR management strategies can be designed to enhance denitrification in the subsurface and reduce N leaching to groundwater, while specifically accounting for lithologic heterogeneity, antecedent soil moisture conditions, and depth to the water table. Our findings are potentially relevant to other systems that experience flooding inundation such as riparian corridors, floodplains, wetlands, and other managed landscapes like dedicated recharge basins.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2026

Data for Zheng et al. (2025), "AquaMEND: Reconciling multiple impacts of salinization on soil carbon biogeochemistry"

Soil salinization, exacerbated by climate change, poses a global threat to coastal ecosystems and soil function. Salinity affects soil carbon cycling by directly impacting microbial activity and indirectly altering soil physicochemical properties, but current models inadequately represent these complexities. This dataset contains the observational and modeling data from Zheng et al. (2025), which described a process-based modeling framework that couples soil solution chemistry with microbial carbon cycling reactions to study the impacts of soil salinization. This conceptual model is implemented numerically into the open-source geochemical program PHREEQC 3.0 (Parkhurst and Appelo, 2013). This dataset consists of: - Figure2_AquaMEND_salinity_buffer: Contains model simulation outputs to assess the impact of three different cation exchange and surface complexation processes on salinity buffering (Fig. 2 from Zheng et al. 2025). - Figure3_Salinity_function: Contains salinity function fitting for literature data (Fig. 3 from Zheng et al. 2025). - Figure4_AquaMEND_microbial_mechanisms: Contains model simulation outputs for testing various microbial process-based hypotheses related to soil salinization, including microbial mortality, carbon use efficiency (CUE), extracellular enzyme activity, and other microbial mechanisms (Fig. 4 from Zheng et al. 2025). - Figure5_AquaMEND_Redox: Contains on model simulation outputs to evaluate shifts among key redox processes, such as aerobic respiration, sulfate reduction, and methanogenesis (Fig.5 from Zheng et al. 2025). - Figure6_AquaMEND_sorption: Contains on model simulation outputs for investigating the effects of salinity on dissolved organic matter (DOM) sorption and desorption processes (Fig. 6 from Zheng et al. 2025). - Figure7_AquaMEND_process_couple: Contains on model simulation outputs for exploring coupled biotic-abiotic processes and their interactions (Fig. 7 from Zheng et al. 2025). - data: Includes datasets used to develop salinity response functions and evaluate salinity buffering capacity. Datasets for MEND model calibration. - database: Contains the `.dat` file required by PHREEQC for model execution. - README.md: A Markdown plain text file describing the computational tools and directories. Files are a mixture of plain text CSV (comma-separated value) and plain text *.dat files written by the model; no special software is required to read them.

EARTH SCIENCE > AGRICULTURE > SOILS > SOIL SALINIT↗
DOE OSTI2021

Cyber–Physical System Security of Distribution Systems

The Information and Communications Technology (ICT) for control and monitoring of power systems is a layer on top of the physical power system infrastructure. The cyber system and physical power system components form a tightly coupled Cyber–Physical System (CPS). Sources of vulnerabilities arise from the computing and communication systems of the cyber–power grid. Cyber intrusions targeting the power grid are serious threats to the reliability of electricity supply that is critical to society and the economy. In a typical Information Technology environment, numerous attack scenarios have shown how unauthorized users can access and manipulate protected information from a network domain. The need for cyber security has led to industry standards that power grids must meet to ensure that the monitoring, operation, and control functions are not disrupted by cyber intrusions. Cyber security technologies such as encryption and authentication have been deployed on the CPS. Intrusion or anomaly detection and mitigation tools developed for power grids are emerging. Furthermore, this survey paper provides the basic concepts of cyber vulnerabilities of distribution systems and CPS security. The important ICT subjects for distribution systems covered in this paper include Supervisory Control And Data Acquisition, Distributed Energy Resources, including renewable energy and smart meters.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2024

Post-Release Survivorship in a New Population of Blanding's Turtles Established Using Headstarted and Directly Released Turtles

Blanding’s Turtles are facing a variety of anthropogenic threats that decrease population viability. We initiated a project to establish a new population of Blanding’s Turtles on a National Wildlife Refuge in Massachusetts using hatchlings obtained from a nearby robust donor population. We released 440 head-started individuals and 401 directly-released hatchlings between 2007–2013 and conducted multiple years of post-release monitoring via aquatic trapping to estimate survival. Between 2014–2021 we released an additional 824 head-started and 433 directly-released individuals and conducted one year of aquatic trapping in 2021 to estimate population size. First year post-release survival of head-started turtles was six times that of directly-released hatchlings (0.72 vs. 0.12, respectively), but annual survival of both groups was 0.78–0.90 in subsequent years. Only 19% of turtles released at <60 mm carapace length (CL) were subsequently recaptured compared to 60% of those released at ≥60 mm CL, supporting 60 mm CL as a target minimum release size. The mean population estimates using two different study designs were 164 and 202, with 91 individuals encountered. Now that turtles released early in the project are approaching reproductive maturity, we recommend resampling and expanding trapping efforts to include more wetlands to assess long-term survival, abundance, and distribution of Blanding’s Turtles in this newly established population. Furthermore, our results, combined with other evaluations of head-starting across the species’ range, add credence to the use of head-starting as a population recovery tool for Blanding’s Turtles.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2021

Validation of Fault Displacements from Dynamic Rupture Simulations against the Observations from the 1992 Landers Earthquake

ABSTRACT Coseismic fault displacements in large earthquakes have caused significant damage to structures and lifelines on and near fault lines. Coseismic displacements represent a real threat, especially to distributed infrastructure systems. For infrastructure systems that can not avoid active faults, engineering displacement demands are defined using probabilistic fault-displacement hazard analyses (PFDHA). However, PFDHA models are sparse and poorly constrained partly due to the scarcity of detailed fault-displacement observations. Advancements in dynamic rupture simulation methods make them an attractive approach to address this important issue. Because fault displacements can be simulated for various geologic conditions as constrained by current knowledge about earthquake processes, they can be used to supplement the observation datasets. In addition to providing on-fault displacements, when used with appropriate constitutive models for the bulk medium, they can capture off-fault distributed inelastic deformations as well. For viable extrapolation, simulations must first be validated against data. In this article, we summarize the calibration and validation of the dynamic rupture model against the observations of the well-documented 1992 Landers earthquake. We defined a preferred model that reproduces several first-order fault-displacement metrics such as the on-fault partition of the total displacement, the mean fault-zone width, and the location of the peak displacement. Simulated ground motions consistent with the observations ensure that all physics important to modeling have been properly parameterized. For the extrapolation, we generated a suite of dynamic rupture models to quantify expected fault-displacement metrics, their intercorrelations, and magnitude dependencies, which are in part supported by the Landers and other recent earthquakes. Our validation and extrapolation exercise paves the way for using dynamic rupture modeling to quantitatively address fault-displacement hazard on a broader scale. The results are promising and are expected to be useful to inform PFDHA model development.

Geochemistry & Geophysics↗
DOE OSTI2019

Developing an engineered therapeutic microbe to release antimicrobial peptides (AMPs)

Antibiotic resistance is a public health threat that will need alternatives in the future to combat it. Antimicrobial peptides (AMPs) have been identified as potential therapeutic candidates compared to traditional antibiotics. A therapeutic microbe has been developed that protects and releases AMPs in an encapsulin cage coupled with a pathogen-sensing detection system. The proposed system uses Escherichia coli as the therapeutic microbe and Pseudomonas aeruginosa as the pathogen.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2019

Marine Biogeochemistry in the Coastal Arctic: Towards Improved Quantitative Understanding of the Controls on Marine Biogeochemical Processes in the Arctic Coastal Zone, and Their Impacts on Climate and the Food Web: A White Paper for DOE’s Regional and Global Model Analysis (RGMA) Program

The Arctic is undergoing unprecedented environmental change and nowhere in the Arctic Ocean is this more evident and directly felt than along the coasts where people live, work, and come to visit. It is widely known that atmospheric CO2 concentrations are increasing, temperatures are rising, sea ice is shrinking, permafrost is warming, and hydrological processes are being altered, although the resulting impacts of such changes on the Arctic marine carbon cycle, greenhouse gas (GHG) fluxes, ecosystems, toxic algal blooms and coastal communities are far from clear. Potential impacts include major threats such as severe ocean acidification (OA) and increased release of methane from coastal shelf seas, as well as shifts in primary production and food-web dynamics, which could in turn further accelerate environmental change.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2019

West Valley Demonstration Project (WVDP) Annual Site Environmental Report (ASER) for Calendar Year 2018

The report, prepared for the U.S. Department of Energy West Valley Demonstration Project office (DOE-WVDP), summarizes the environmental protection program at the WVDP for calendar year (CY) 2018. Monitoring and surveillance of the facilities used by the DOE are conducted to verify protection of public health and safety and the environment. The report is a key component of DOE’s effort to keep the public informed of environmental conditions at the WVDP. The quality assurance protocols applied to the environmental monitoring program ensure the validity and accuracy of the monitoring data. In addition to demonstrating compliance with environmental laws, regulations, and directives, evaluation of data collected in 2018 continued to indicate that WVDP activities pose no threat to public health or safety, or to the environment.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2019

Development of a statistical model (tool) for classifying buried object detectability

To improve warfighter safety under changing requirements, assets must be adaptable and able to detect and mark buried hazards. Current GPR systems would benefit by improvements in speed, usability, and operational versatility to enhance operational effectiveness for all platforms and missions. Our sponsor requests that LLNL research GPR methodologies and approaches to allow for specific improvements to be made in those areas. MiRadar uses a novel multi-static array architecture coupled with tomographic processing to focus returned energy from the real (physical) and synthetic (motion-derived) apertures. 3D streaming movies of the subsurface are easily interpreted, slashing training times. Real-time processing codes enable imaging and operation three times faster; automated volumetric detection algorithms warn of possible hazards. In a two-week trial, multiple vehicle-mounted arrays and a new ultralightweight architecture on a small, unmanned aircraft system executed 498 runs, collecting over 400km of data on 13 preemplaced lanes containing 384 simulated buried threats.

42 ENGINEERING↗
DOE OSTI2019

Testing and evaluation of the Sandia Smart Pre-concentrator using a vapor generation system

Sandia National Laboratories (SNL) was contracted by the Defense Threat Reduction Agency (DTRA), through KBRwyle to perform testing and evaluation of the SNL Smart Pre-concentrator (SPC) system and a COTS FTIR system procured by DTRA through KBRwyle. Two common chemical warfare agent simulants, dimethyl methylphosphonate and triethyl phosphate were selected as the compounds of interest. SNL tested both systems using a COTS vapor generation system, capable of delivering known concentrations of specific chemical compounds to both detection systems, with Sandia responsible for the SPC system. Both systems were measured against COTS sorbent collection tubes analyzed by SNL via a laboratory GCMS system. Concentrations measured from tubes upstream from the FTIR system differed from the expected concentrations, while downstream tubes were mostly within 20% of the target concentration.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
DOE OSTI2019

Building Island Resilience through the Energy, Water, Food Nexus

Islands face unique and often exaggerated threats from climate change. Additionally, the very nature of islands creates greater dependence on imported food and energy resources. Extreme events have highlighted weaknesses in island energy, water, and food systems as a result of utility outages and shipping delays. These events have challenged islands to improve their resilience and seek new strategies to ensure energy, water, and food security. One such island is Sint Eustatius, which has constructed a first of its kind solar park providing reliable energy, community agriculture, and harvested rainwater for irrigation This paper highlights integrated strategies to help islands enhance resilience across the energy, water, food nexus.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2019

Polarized Radar for Detection and Automatic Non-Visual Assessment of Unmanned Aerial Systems

This Laboratory Directed Research and Development (LDRD) effort performed fundamental Research and Development (R&D) to develop a robust radar processing algorithm capable of assessing the difference between an Unmanned Aerial System (UAS) and a biological target such as a bird, based on mathematics applied to the polarized radar returns of the target object, alone. The current threats of using such a UAS as a delivery platform for a host of destructive components is a major concern for the protection of various assets. Most recently, on 14th Sept. 2019, dozens of suicide or kamikaze drones (UAV-X) coordinated an attack on two Saudi oil facilities that demonstrated the potential to disrupt global oil supplies. While radar-based UAS detection systems can detect UAS at ranges greater than 1-km, the issues of excessive Nuisance/False Alarm Rates (NAR/FAR) from natural sources (birds in particular) has not been sufficiently addressed. In this effort we describe and utilize the Adaptive Polarization Difference Imaging-based (APDI) algorithms for the detection and automatic non-visual assessment of Unmanned Aerial System applications. Originally developed for optical imaging and sensing of polarization information in nature, the algorithms developed here are modified to serve for the target detection purposes in counter-UAS (cUAS) environments. We exploit the polarization statistics of the observing scene for detection and identification of changes within the scene and assess from these changes for UAS/bird classifications. Several cases are considered from independent data sources, including numerically generated data, anechoic chamber data as well as experimental radar data, to show the applicability of the techniques developed here. The methods developed in this effort are designed to be used in cUAS setups but have shown promise for a multitude of other radar-based classification uses as well.

47 OTHER INSTRUMENTATION↗
DOE OSTI2019

Novel Chemistry to Support the Detection of Advanced Chemical Agents

Recent news reports coming from Asia and the UK have highlighted the emerging threats of Non-Traditional Agents (NTAs) to national security. The UK incident underscores how NTAs may linger in the environment and at trace. Building on Sandia's extensive analytical chemistry work in this field, a polysilphenylene analog of Sandia's proprietary DKAP polymer coatings was synthesized and evaluated for high temperature operation. Initial test results are inconclusive as to the improved thermal stability of the new polymer with TGA/DSC results indicating a lower glass transition go temperature for the new "Hot DKAP" material and a similar to slightly lower start to mass loss for "Hot DKAP", but slower degradation rate in clean dry air. Additional testing with a TGA-MS system to identify what the fragments lost as a function of temperature is still needed to fully characterize the materials thermal properties. In addition, the material still needs to be evaluated for thermodynamic properties for analytes of interest using either GC or SPC coated devices.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2019

Cas9 Protein Post-translational Modifications (PTMs): A Potential Biomarker of Gene-editing

The clustered regularly interspaced short palindromic repeats (CRISPR) arrays and the CRISPR associated (Cas) proteins comprise a prevalent prokaryotic and archaeal adaptive immune system. The CRISPR/Cas9 system has been coopted for and become the ubiquitous gene-editing system due to the simplicity of requiring minimally the CRISPR RNA components and Cas9 protein for specific DNA sequence alteration. CRISPR/Cas9 has been extensively used for gene-editing a wide range of species with human patient trails currently underway. However, unsanctioned genome editing is a national security and public health threat that can cause serious permanent illness and death as well as having the potential for very long-lasting effects over generations due to genetic inheritance of the gene-edit. While the Cas9 protein would appear as a highly specific indicator of exposure to gene-editing reagents, the bacterial origins of CRISPR/Cas9 creates a daunting problem for detection. Bacterial Cas9 would then generate false-positives for detecting gene-editing by conventional molecular biology techniques. Antibody-based assays for Cas9 would be unable to distinguish between Cas9 expressed in human cells for gene-editing and highly common unrelated Cas9 from bacterial infections. Posttranslational modifications of proteins are highly cell specific and hold the potential for discerning the cellular origins of a Cas9 protein and the differentiating between bacterial and gene-editing CRISPR/Cas9. The work described herein is in progress towards the identification of Cas9 post-translational modifications from bacterial and human cell expressed Cas9.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2019

Gas-Electrical Grid Coordination for Cross Infrastructure Resilience Enhancement

An electric power grid is exceedingly faced with extreme events, such as physical attacks and natural disasters. In comparison, the underground natural gas pipeline-based transportation network is considered less vulnerable to such environmental threats. We consider that the overhead power transmissions can be hardened by replacing segments of electric power system with underground natural gas pipelines as an energy transportation system to counter effect extreme events which can damage interdependent infrastructures severely. This project investigates an extension of the power system planning problem considering extreme events and identifies the feasibility of solving this problem with advanced modeling and optimization methods. The proposed planning framework is formulated as a two-stage optimization problem. It is found that the integrated planning introduces the additional cost of pipeline planning and the operation constraints into the power system planning. However, gas pipelines are generally less exposed to extreme events, which can provide a more resilient power transmission for supplying the electrical loads. It is with this potential for enhancing the power grid resilience that the proposed integrated expansion of electricity and natural gas system is considered an optimal layout for the transportation of energy.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2019

Pileup Calculations for GADRAS

This report describes how random pileup calculations are performed by the Gamma Detector Response and Analysis Software (GADRAS) Version 19.1. The computational approach and examples are presented for gamma-ray detectors with and without pileup rejectors. This pileup algorithm executes more quickly and the results are more accurate than previous versions of GADRAS. The detector response function can be refined to characterize distortions in peak shapes that occur at high-count rates. The empirical refinement can also be applied to describe the response of partially-effective pileup rejectors. Implications are discussed for the analysis of both static measurements and dynamic collections of the type acquired with radiation portals. ACKNOWLEDGEMENTS This work was funded by the Defense Threat Reduction Agency (DTRA) and the Department of Homeland Security (DHS) Counter Weapons of Mass Destruction (CWMD) office.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗